Combined safety cranking device, clutch, and pulley for explosive-engines.



G. B. WILSON.

COMBINED SAFETY GRANKING DEVICE, CLUTCH, AND FULL 'APPLIOATION FILED 001 13. 1911.

Patented Aug. 12, 1913.

BY FOR BXPLGSWE ENGINES.

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GEORGE E. WILSON, OI STILLWATER, MINNESOTA, ASSIGNOR TU IVI. RUE/[ELY COM- PANY, 0F LAPORTE, INDIANA, A CGRPORATION OF INDIANA.

COMBINED SAFETY CEANKING DEVICE, CLUTCH, AND PULLEY FOR EXPLOSIVE- ENGINES.

Patented Aug. 12,1913.

Application filed October 13, 1811. Serial No. 654,494.

To all whom it may concern:

Be it lmown that I, Greener E. Winsos, a citizen of the United States, residing at Stillwater, in the county of W'ashington and State of Minnesota, have invented certain new and useful Improvements in Combined Safety Cranking Devices, Clutches, and Pulleys for Explosive-Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention has for its object to provide (i-simple and efficient combined safety cranking device. clutch and pulley for use in connection with explosive engines, and especiu'lly adapted for use in connection with the explosive engines of gasolene or oil tractors.

To the above ends, generally stated, the invent-ion consists of the novel devices and combinations of devices hereinafter de scribed and defined in the claims.

The invention is illustrated in the accom: panying drawings wherein like characters indicate like parts throughout the several views.

Referring to the drawings, Figure 1 is a view in horizontal section showing the improved device; Fig. 2 is a side elevation showing the improved pulley clutch and satety cranking device, some parts being broken away; and Fig. 3 is a detail partly in vertical section and partly in full elevation showing the starting crank applied to the crank shaft and crank tripping clutches.

In the preferred construction illustrated, the engine crank shaft& is keyed, or has othenwise rigidly secured-to one end, a fric- Lion clutch disk 2 having a projecting hub in which a bushing 3 is rigidly secured. The outerend of the said hub and bushing are formed with ratchet teeth 4;, preferably two in number located diametrically at lopposite points. A pulley 5 is provided with a long sleeve-like hub 6 mounted to rotate on the shaft 1. Clutch levers 7 are interme- Tdiately pivoted in the openings formed in the web of the pulley 5 and provided with brake shoes 8 adapted to press the disk 2 against brake shoes 9 secured on the face'ofli the web of the said pulley. Ashipper sleeve 10 is mounted to slide upon but to rotate with the pulley hub 6, and this sleeve is connected by links 11 to the adjacent ends of the clutch lever 7 The usual or any suitable means may beprovided for imparting slidnoted. Normally, the teeth of the ratchet wheel 12 are engaged by one or more retaining pawls 14 which, as shown, are pivoted toinwardly projecting arms 15 rigidly secured to the rim of the pulley As a preferred arrangement for yieldingly holding the retaining pawls 14:, small bolts 16 are pivoted thereto and are arranged to slide through reaction blocks 17 that are'piv'oted to the respective arms 15. Coiled springs are Placed 011 e'bolts' '16 and comprssed between said pawls and reaction. blockg' 17 When the pawls are set by hand, as shown in full lines in #Fig. 2, they are yieldi-ngly held for engagement with the teeth of the ratchet wheel 12-, but when moved by hand into an e'xtrenie position shown by dot-ted lines in Fig.2, they wiill be spring held in in: operative positions, so that noise will not be produced when the engine crank shaftis driven while the pulley 5 remains stationary.

The starting crank 19 is provided with a head 20. formed with axially projecting centering pin 21 and with diametrically opposing ratchet teeth 22. The centering pin 551 is shown as formed with sections of relatively large and small diameter to fit the large and small end portions of thebushings 3, but this specific construction, as well as the use "of the bushings are only matters of detail, the said bushings being used as a convenience in construction. The ratchet teeth 4 are also formed in the end of the disk hub 2 and in the bushings 3, as a matter'of preferenceybut in eitect, and a broad point o-fview, the said ratchet teeth are formed on a part 0% the crank shaft 1. Preferably. the pulley '5 is provided at itsinner edge with an enlarged guard hangs 5 to prevent the 21 1111 the crank releasing action above described, the force required to overcome the sleeve of an operator, for example, from being caught by the clutch lever 'Z or links ll, When the starting cr'ankf'is applied in working position as 'shown in Figs. 1 and 3, its ratchet teeth 22 are engaged with the crank shaft ratchet teeth 4 and with the teeth 2- of the gripping ratchet 12, which teeth l and 13 are then allned radially.

When the engine is to be cranked, the clutch is open so as to permit the pulley 5 to stand still. If the driving belt happens to be on the pulley atsuch time, so much the better. Y The engine is cranked by rotation of its shaft in direction of the arrow marked on Fig. 2,.and. if the belt is not on the pulley, the pulley yvill probably be givenmore or less movement in the same direction, by friction in the journal, butit may sometimes remain approximately stationary. In the cranking action, the, ratchet wheel 12' moves with the crank shaft, but if the crank shaft be given a reverse moyement by a back explosion, the pawls ll will hold the ratchet wheel against such backward movement and its ratchet or clutch teeth 13 will then act as cams on the teeth 22 of the starting crank, and will. instantly force the said teeth 22 out of engagement with the teeth 4 and 13 and thus disconnect the said starting crank from the crank shaft. This, as is evident, will efi'ectually prevent breaking of arms, or other accidents such as frequently occur when-a back explosion takes place in-cranking the engine. lt-is also im portant to note that the length of the centering pin 21 of the starting crank is such in respect toits seats in the bushing 5 that the said pin wlllbe forced out of engagement with the said seats when the ratchet or clutch teeth 4, 13, and 22-are disengaged, as above described. This is important because it causes the starting crank to drop out of engagement with its seat in the engine crank shaft? and hence preventsaccidental reengagement of the said clutch teeth following an initial backward movement due toja back explosion.

inertia of the pulley is-such that it holds ehe ratchet wheel 12 either stationary or drags backward thereon so thatthe releas- -ing'action takes place-as stated. Vihen the helt .ison the pulley, the said pulley will, of course, remain absolutely stationary.

The expression relatively stationary as applied to the pulley, is herein used ;in a liberal sense, to mean that the said pulley either stands still or drags backward with sufficient force to release the starting crank from the cooperatingclutch members. The

so-called engine crank shaft may be an integral part of the engine crank shaft proper 01 it may be a shaft coupled thereto in an j suitable way and driven thereby.

The elements 4, Band 22 herein speciti- ,iially referred ,to, as ratchet teeth, constitute cooperating half clutches, which are adapt-' ed to be engaged and disengaged, as above described. I

-What 1- claim is;

1. The combination with a crank shaft, a pulley and a clutch for connecting and disconnecting said shaft and pulley, said shaft having a crank engaging member, of a starting crank cletacliably engageable with the crank engaging member ofsaid shaft, said pulley adapted to remain relatively stationary with respect to said shaft during cranking and when said clutch is disen gaged, and a crank releasing device having a base of reaction against said pulley and operative to release said crank from the v crank engaging member of said shaft when said shaft is rotated backward in respectto said pulley.

2. The combination with a crank shaft, a pulley thereomand' a clutch for connecting and disconnecting said shaft and pulley, said shaft having a crank engaging half clutch, of a starting crank having a half. clutch detachably engageable with the half .clutch of said shaftl by lateral movements longitudinally of said shaft, said pulleyadapted to remain relatively stationary with respect to saidshaft duringcranking and. y

when said clutch is disengaged, and a crank releasing device operative to disconnect said starting crank from said shaft, when said shaft is rotated backward in respect to said pulley. I

3. lhe combination with a crank shaft, a pulley loose on said shaft, and a clutch for connecting and disconnecting saidshaft and pulley, at will, a starting crank having a half clutch, a ratchet wheel loose in respect to said pulley and shaft, said ratchet wheel, and shaft, having crank engaging half clutches adapted to be in position for en'- gagement with a half clutch of said startingcrank, and a yielding pawl on said pul ley operative on said ratchet wheel to retard backward movement thereof and thereby release said cr'ank, whensaid shaft is retated backward in respect to said pulley.

l The combination with a crank shaft, a

pulley loose thereon, and a clutch for con;

nectmg and disconnecting the; two at will, of a ratchet Wheel loose in respect to said shaft and pulley but axially alined therewith, a starting crank having a half clutch,

half clutches on said ratchet wheel and on said crank shaft adapted to be positioned for engagement with the half clutch of said starting crank. in the starting action, and a yielding'pawl on said pulley operative on the teeth of said ratchet wheel to retard movement thereof and release said crank, when said engineshaft is given an initial backward movement,-

5. The combination with a crank shaft, a pulley loose thereon, and a clutch for connecting and disconnecting the two at will, of a ratchet wheel loose in respect to said shaft and pulley but axiallyalined therewith, a starting crank having a half clutch, half clutches on said ratchet wheel and on said crank shaft adapted, to be positioned for engagement with the half clutch of said starting crank in the starting action, anda yielding pawl on said pulley operative on the teeth of said ratchet Wheel to retard movement thereof and release said crank,

when said engine shaft is given an initial. backward moxeinent, the said starting crank having a centering pin engagcable with a seat in said crank shaft and of such length that it will be disengaged from its seat When the above noted half clutches are disengaged.

In testimony whereof I aflix my signature in presence of two Witnesses.

GEORGE E. WILSON.

Witnesses:

BERNIOE G. WHEELER, HARRY D. KILcoRE.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. 0. 

